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Current perspectives of viral
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作者 Daisuke Usuda Yuki Kaneoka +23 位作者 Rikuo Ono Masashi Kato Yuto Sugawara Runa Shimizu Tomotari Inami Eri Nakajima Shiho Tsuge Riki Sakurai Kenji Kawai Shun Matsubara Risa Tanaka Makoto Suzuki Shintaro Shimozawa Yuta Hotchi Ippei Osugi Risa Katou Sakurako Ito Kentaro Mishima Akihiko Kondo Keiko Mizuno Hiroki Takami Takayuki Komatsu Tomohisa Nomura Manabu Sugita 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2402-2417,共16页
Viral hepatitis represents a major danger to public health,and is a globally leading cause of death.The five liver-specific viruses:Hepatitis A virus,hepatitis B virus,hepatitis C virus,hepatitis D virus,and hepatitis... Viral hepatitis represents a major danger to public health,and is a globally leading cause of death.The five liver-specific viruses:Hepatitis A virus,hepatitis B virus,hepatitis C virus,hepatitis D virus,and hepatitis E virus,each have their own unique epidemiology,structural biology,transmission,endemic patterns,risk of liver complications,and response to antiviral therapies.There remain few options for treatment,in spite of the increasing prevalence of viral-hepatitiscaused liver disease.Furthermore,chronic viral hepatitis is a leading worldwide cause of both liver-related morbidity and mortality,even though effective treatments are available that could reduce or prevent most patients’complications.In 2016,the World Health Organization released its plan to eliminate viral hepatitis as a public health threat by the year 2030,along with a discussion of current gaps and prospects for both regional and global eradication of viral hepatitis.Today,treatment is sufficiently able to prevent the disease from reaching advanced phases.However,future therapies must be extremely safe,and should ideally limit the period of treatment necessary.A better understanding of pathogenesis will prove beneficial in the development of potential treatment strategies targeting infections by viral hepatitis.This review aims to summarize the current state of knowledge on each type of viral hepatitis,together with major innovations. 展开更多
关键词 Hepatitis a virus Hepatitis B virus Hepatitis c virus Hepatitis D virus Hepatitis E virus current perspectives
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Strong electronic coupling of CoNi and N-doped-carbon for efficient urea-assisted H2 production at a large current density 被引量:1
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作者 Guangfu Qian Jinli Chen +3 位作者 Wenjie Jiang Tianqi Yu Kexin Tan Shibin Yin 《Carbon Energy》 SCIE EI CAS CSCD 2023年第12期187-199,共13页
Exploiting efficient urea oxidation reaction(UOR)and hydrogen evolution reaction(HER)catalysts are significant for energy-saving H2 production through urea-assisted water electrolysis,but it is still challenging.Herei... Exploiting efficient urea oxidation reaction(UOR)and hydrogen evolution reaction(HER)catalysts are significant for energy-saving H2 production through urea-assisted water electrolysis,but it is still challenging.Herein,carbon-encapsulated CoNi coupled with CoNiMoO(CoNi@CN-CoNiMoO)is prepared by solvothermal method and calcination to enhance the activity/stability of urea-assisted water electrolysis at large current density.It exhibits good activity for UOR(E10/1,000=1.29/1.40 V)and HER(E-10/-1000=-45/-245 mV)in 1.0 M KOH+0.5 M urea solution.For the UOR||HER system,CoNi@CN-CoNiMoO only needs 1.58 V at 500 mA cm-2 and shows good stability.Density functional theory calculation suggests that the strong electronic interaction at the interface between NiCo alloy and N-doping-carbon layers can optimize the adsorption/desorption energy of UOR/HER intermediates and accelerate the water dissociation,which can expedite urea decomposition and Volmer step,thus increasing the UOR and HER activity,respectively.This work provides a new solution to design UOR/HER catalysts for H2 production through urea-assisted water electrolysis. 展开更多
关键词 carbon-encapsulated structure catalyst hydrogen production large current density urea-assisted water electrolysis
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大面积脑梗死患者血清Visfatin、TN-C、IL-17水平与神经功能缺损程度的相关性及对预后的预测价值
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作者 李小磊 李华丽 石伟纲 《海南医学》 CAS 2024年第5期614-619,共6页
目的 探讨大面积脑梗死(LHI)患者血清内脂素(Visfatin)、肌腱蛋白C (TN-C)、白介素-17 (IL-17)水平与神经功能缺损程度的相关性及对患者预后的预测价值。方法 前瞻性选取2020年1月至2023年1月平顶山市第一人民医院收治的80例LHI患者作为... 目的 探讨大面积脑梗死(LHI)患者血清内脂素(Visfatin)、肌腱蛋白C (TN-C)、白介素-17 (IL-17)水平与神经功能缺损程度的相关性及对患者预后的预测价值。方法 前瞻性选取2020年1月至2023年1月平顶山市第一人民医院收治的80例LHI患者作为LHI组,另选取同期80例非大面积急性脑梗死(ACI)患者作为非LHI组,同期80例健康志愿者作为对照组。比较三组研究对象入院(体检)时的血清Visfatin、TN-C、IL-17水平,并比较LHI组不同神经功能缺损程度患者的血清Visfatin、TN-C、IL-17水平,采用Spearman相关系数分析血清Visfatin、TN-C、IL-17水平与LHI神经功能缺损程度的相关性。比较LHI组不同预后患者入院时血清Visfatin、TN-C、IL-17水平,通过受试者工作特征曲线(ROC)分析血清Visfatin、TN-C、IL-17水平预测预后的价值,采用KM生存曲线分析不同血清Visfatin、TN-C、IL-17水平患者3个月存活情况。结果 LHI组患者入院时的血清Visfatin、TN-C、IL-17水平分别为(86.74±25.17)μg/L、(81.45±20.67)μg/L、(118.19±28.26) pg/mL,明显高于非LHI组的(51.63±16.24)μg/L、(61.29±15.16)μg/L、(76.70±15.49) pg/mL和对照组的(7.71±1.59)μg/L、(19.61±7.38)μg/L、(29.51±6.02) pg/mL,且非LHI组患者的血清Visfatin、TN-C、IL-17水平明显高于对照组,差异均具有统计学意义(P<0.05);LHI组神经功能缺损程度重度患者入院时的血清Visfatin、TN-C、IL-17水平分别为(98.71±18.25)μg/L、(95.38±16.84)μg/L、(135.71±26.03) pg/mL,明显高于中度患者的(79.17±15.61)μg/L、(72.64±14.10)μg/L、(107.11±22.49) pg/mL,差异均具有统计学意义(P<0.05);经Spearman相关分析法分析结果显示,入院时血清Visfatin、TN-C、IL-17水平与LHI患者神经功能缺损程度呈正相关(P<0.05);LHI组预后不良患者入院时的血清Visfatin、TN-C、IL-17水平分别为(101.25±19.17)μg/L、(98.74±17.43)μg/L、(140.71±28.01) pg/mL,明显高于预后良好患者的(78.49±16.20)μg/L、(71.62±15.76)μg/L、(105.38±24.26) pg/mL,差异均有统计学意义(P<0.05);经ROC分析结果显示,入院时血清Visfatin、TN-C、IL-17水平联合预测LHI预后不良的曲线下面积(AUC)为0.951 (95%CI:0.878~0.987),大于三项指标单独预测的AUC (P<0.05);LHI组入院时血清Visfatin、TN-C、IL-17高水平患者3个月后存活率分别为74.29%、76.32%、70.97%,明显低于血清Visfatin、TN-C、IL-17低水平患者的93.33%、92.86%、93.88%,差异均有统计学意义(P<0.05)。结论 LHI患者血清Visfatin、TN-C、IL-17水平明显升高,且与神经功能缺损程度呈正相关,联合检测各指标可为临床预测患者预后提供可靠依据。 展开更多
关键词 大面积脑梗死 内脂素 肌腱蛋白c 白介素-17 神经功能缺损 预后
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SiC gate-controlled bipolar field effect composite transistor with polysilicon region for improving on-state current
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作者 段宝兴 罗开顺 杨银堂 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期657-662,共6页
A novel silicon carbide gate-controlled bipolar field effect composite transistor with poly silicon region(SiC GCBTP)is proposed.Different from the traditional electrode connection mode of SiC vertical diffused MOS(VD... A novel silicon carbide gate-controlled bipolar field effect composite transistor with poly silicon region(SiC GCBTP)is proposed.Different from the traditional electrode connection mode of SiC vertical diffused MOS(VDMOS),the P+region of P-well is connected with the gate in SiC GCBTP,and the polysilicon region is added between the P+region and the gate.By this method,additional minority carriers can be injected into the drift region at on-state,and the distribution of minority carriers in the drift region will be optimized,so the on-state current is increased.In terms of static characteristics,it has the same high breakdown voltage(811 V)as SiC VDMOS whose length of drift is 5.5μm.The on-state current of SiC GCBTP is 2.47×10^(-3)A/μm(V_(G)=10 V,V_(D)=10 V)which is 5.7 times of that of SiC IGBT and 36.4 times of that of SiC VDMOS.In terms of dynamic characteristics,the turn-on time of SiC GCBTP is only 0.425 ns.And the turn-off time of SiC GCBTP is similar to that of SIC insulated gate bipolar transistor(IGBT),which is 114.72 ns. 展开更多
关键词 Si c power device on-state current BIPOLaR vertical diffused MOS(VDMOS) insulated gate bipolar transistor(IGBT)
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A CAD oriented quasi-analytical large-signal drain current model for 4H-SiC MESFETs 被引量:3
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作者 曹全君 张义门 +4 位作者 张玉明 吕红亮 王悦湖 常远程 汤晓燕 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第4期1097-1100,共4页
This paper reports that a 4H-SiC MESFET (Metal Semiconductor Field Effect Transistor) large signal drain current model based on physical expressions has been developed to be used in CAD tools. The form of drain curr... This paper reports that a 4H-SiC MESFET (Metal Semiconductor Field Effect Transistor) large signal drain current model based on physical expressions has been developed to be used in CAD tools. The form of drain current model is based on semi-empirical MESFET model, and all parameters in this model are determined by physical parameters of 4H-SiC MESFET. The verification of the present model embedded in CAD tools is made, which shows a good agreement with measured data of large signal DC I-V characteristics, PAE (power added efficiency), output power and gain. 展开更多
关键词 4H-Sic MESFET drain current model caD large signal
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Electrical Performance Study of a Large Area Multicrystalline Silicon Solar Cell Using a Current Shunt and a Micropotentiometer 被引量:1
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作者 Hala Mohamed Abdel Mageed Ahmed Faheem Zobaa +4 位作者 Ahmed Ghitas Mohamed Helmy Abdel Raouf Mohamed Sabry Abla Hosni Abd El-Rahman Mohamed Mamdouh Abdel Aziz 《Engineering(科研)》 2010年第4期263-269,共7页
In this paper, a new technique using a Current Shunt and a Micropotentiometer has been used to study the electrical performance of a large area multicrystalline silicon solar cell at outdoor conditions. The electrical... In this paper, a new technique using a Current Shunt and a Micropotentiometer has been used to study the electrical performance of a large area multicrystalline silicon solar cell at outdoor conditions. The electrical performance is mainly described by measuring both cell short circuit current and open circuit voltage. The measurements of this cell by using multimeters suffer from some problems because the cell has high current intensity with low output voltage. So, the solar cell short circuit current values are obtained by measuring the voltage developed across a known resistance Current Shunt. Samples of the obtained current values are accurately calibrated by using a Micropotentiometer (μpot) thermal element (TE) to validate this new measuring technique. Moreover, the solar cell open circuit voltage has been measured. Besides, the cell output power has been calculated and can be correlated with the measured incident radiation. 展开更多
关键词 large area MULTIcRYSTaLLINE Silicon Solar cell current Measurements calibration current SHUNT Micropotentiometer SHORT cIRcUIT current Open cIRcUIT VOLTaGE
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Temperature Effects on the Electrical Performance of Large Area Multicrystalline Silicon Solar Cells Using the Current Shunt Measuring Technique 被引量:1
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作者 Hala Mohamed Abdel Mageed Ahmed Faheem Zobaa +2 位作者 Mohamed Helmy Abdel Raouf Abla Hosni Abd El-Rahman Mohamed Mamdouh Abdel Aziz 《Engineering(科研)》 2010年第11期888-894,共7页
The temperature effects on the electrical performance of a large area multicrystalline silicon solar cell with back-contact technology have been studied in a desert area under ambient conditions using the current shun... The temperature effects on the electrical performance of a large area multicrystalline silicon solar cell with back-contact technology have been studied in a desert area under ambient conditions using the current shunt measuring technique. Therefore, most of the problems encountered with traditional measuring techniques are avoided. The temperature dependency of the current shunt from 5oC up to 50oC has been investigated. Its temperature coefficient proves to be negligible which means that the temperature dependency of the solar cell is completely independent of the current shunt. The solar module installed in a tilted position at the optimum angle of the location, has been tested in two different seasons (winter and summer). The obtained solar cell short circuit current, open circuit voltage and output power are correlated with the measured incident radiation in both seasons and all results are discussed. 展开更多
关键词 large area MULTIcRYSTaLLINE Silicon Solar cell current SHUNT Measuring Technique Temperature Effects SHORT cIRcUIT current Open cIRcUIT Voltage accumulated Power INcIDENT Radiation
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Study on scour around vertical large-size cylinder base due to combined action of wave and current 被引量:1
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作者 姜萌 李林普 +1 位作者 韩丽华 张日向 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第4期45-50,共6页
Based on the mechanism of local scour around vertical large-sized cylinder due to combined action of wave and current,the sour morphology,scour process and the maximum scour depth around the cylinders are studied expe... Based on the mechanism of local scour around vertical large-sized cylinder due to combined action of wave and current,the sour morphology,scour process and the maximum scour depth around the cylinders are studied experimentally.The influence of various ocean environmental parameters on local scour around the cylinder is considered in physical model test.The experimental results indicate that the principal effect factors on the scour in fine-sand seabed are wave height,wavelength,current velocity,ratio of diameter to wavelength and ratio of depth to wavelength when the ratio of cylinder diameter to wavelength is from 0.2 to 0.8.In this paper,dimensional analysis theory is utilized to establish a theoretical equation for forecasting maximum scour depth around large-sized round cylinder base due to the combined action of wave and current.The results computed with the theoretical equation are compared with the experimental results,and found to be in good consistency.The results in this studies can be used to estimate the maximum sour depth around analogous structures. 展开更多
关键词 OFFSHORE combined action of wave and current large-sized cylinder local scour
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Controllable synthesis of a self-assembled ultralow Ru,Ni-doped Fe_(2)O_(3) lily as a bifunctional electrocatalyst for large-current-density alkaline seawater electrolysis
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作者 Tong Cui Xuejun Zhai +5 位作者 Lili Guo Jing-Qi Chi Yu Zhang Jiawei Zhu Xuemei Sun Lei Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2202-2211,共10页
Highly efficient and stable bifunctional electrocatalysts that can be used for large-current-density electrolysis of alkaline seawater are highly desirable for carbon-neutral economies,but their facile and controllabl... Highly efficient and stable bifunctional electrocatalysts that can be used for large-current-density electrolysis of alkaline seawater are highly desirable for carbon-neutral economies,but their facile and controllable synthesis remains a challenge.Here,self-assembled ultralow Ru,Ni-doped Fe_(2)O_(3) with a lily shaped morphology was synthesized on iron foam(RuNi-Fe_(2)O_(3)/IF)via a facile one-step hydrothermal process,in which the intact lily shaped RuNi-Fe_(2)O_(3)/IF was obtained by adjusting the ratio of Ru/Ni.Benefitting from the Ru/Ni chemical substitution,the as-synthesized RuNi-Fe_(2)O_(3)/IF can act as free-standing dual-function electrodes that are applied to electrocatalysis for the hydrogen evolution(HER)and oxygen evolution reactions(OER)in 1.0 mol L^(-1) KOH,requiring an overpotential of 75.0 mV to drive 100 mA cm^(-2) for HER and 329.0 mV for OER.Moreover,the overall water splitting catalyzed by RuNi-Fe_(2)O_(3)/IF only demands ultralow cell voltages of 1.66 and 1.73 V to drive 100 mA cm^(-2) in 1.0 mol L^(-1) KOH and 1.0 mol L^(-1) KOH seawater electrolytes,respectively.The electrodes show remarkable long-term durability,maintaining current densities exceeding 100 mA cm^(-2) for more than 100 h and thus outperforming the two-electrode system composed of noble catalysts.This work provides an efficient,economical method to synthesize self-standing bifunctional electrodes for large-current-density alkaline seawater electrolysis,which is of significant importance for ecological protection and energy exploitation. 展开更多
关键词 RuNi-Fe_(2)O_(3)/IF Lily shape Bifunctional electrocatalyst alkaline seawater splitting large current density
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Applied the Large Scale Particle Image Velocimetry Technique for Measurement the Velocity of Gravity Currents in the Laboratory
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作者 Dhafar Ibrahim Ahmed Noureddine Latrache Blaise Nsom 《Journal of Water Resource and Protection》 2015年第8期597-604,共8页
This study includes a series of laboratory experiments for investigated the gravity current of fresh water with density ρ-?ρ, and initial speed u0 upon the free surface of an ambient liquid (salty water) with densi... This study includes a series of laboratory experiments for investigated the gravity current of fresh water with density ρ-?ρ, and initial speed u0 upon the free surface of an ambient liquid (salty water) with density ρ at rest in a basin. It’s have been presented to illuminate the dominant flow and transport phenomena in the presence of river, stream and wetland ecology, stream corridor restoration, in the case of accidental pollution spills. The characterized of the local kinematic field, i.e. the local velocity and vorticity fields, the measurement methods include particle image velocimetry (PIV) at the water surface using a technique similar to large scale of particle image velocimetry (LSPIV). 展开更多
关键词 Gravity currentS IMaGE Processing large-Scale Particle IMaGE VELOcIMETRY TEcHNIQUE SPaTIOTEMPORaL DIaGRaMS TEcHNIQUE
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Saturation Ion Current Densities in Inductively Coupled Hydrogen Plasma Produced by Large-Power Radio Frequency Generator
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作者 WANG Songbai LEI Guangjiu +3 位作者 BI Zhenhua H. GHOMI YANG Size LIU Dongping 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第9期907-911,共5页
An experimental investigation of the saturation ion current densities (Jions) in hydrogen inductively coupled plasma (ICP) produced by a large-power (2-32 kW) radio frequency (RF) generator is reported, then s... An experimental investigation of the saturation ion current densities (Jions) in hydrogen inductively coupled plasma (ICP) produced by a large-power (2-32 kW) radio frequency (RF) generator is reported, then some reasonable explanations are given out. With the increase of RF power, the experimental results show three stages: in the first stage (2-14 kW), the electron temperature will rise with the increase of RF power in the ICP, thus, the Jions increases continually as the electron temperature rises in the ICP. In the second stage (14 20 kW), as some H- ions lead to the mutual neutralization (MN), the slope of Jio^s variation firstly decreases then increases. In the third stage (20-32 kW), both the electronic detachment (ED) and the associative detachment (AD) in the ICP result in the destruction of H- ions, therefore, the increased amplitude of the Jions in the third stage is weaker than the one in the first stage. In addition, with the equivalent transformer model, we successfully Explain that the Jions at different radial locations in ICP has the same rule. Finally, it is found that the Jions has nothing to do with the outer/inner puffing gas pressure ratio, which is attributed to the high-speed movement of hydrogen molecules. 展开更多
关键词 saturation ion current densities large-power RF generator outer/innerpuffing gas pressure ratio H- ion transformer model
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结合SAM大模型和数学形态学的历史地图水系信息提取方法 被引量:1
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作者 赵飞 李兆正 +6 位作者 甘泉 高祖瑜 王湛初 杜清运 王振声 沈洋 潘威 《测绘学报》 EI CSCD 北大核心 2024年第4期761-772,共12页
历史地图记载着丰富的历史地理信息,能够帮助了解历史规律,为当代发展提供借鉴。不同于现代地图、遥感影像等数据,历史地图保存时间久,存在留存数量少、图像精度低等问题,地图符号也与现代有所差异,因此信息难以被高效提取。针对该问题... 历史地图记载着丰富的历史地理信息,能够帮助了解历史规律,为当代发展提供借鉴。不同于现代地图、遥感影像等数据,历史地图保存时间久,存在留存数量少、图像精度低等问题,地图符号也与现代有所差异,因此信息难以被高效提取。针对该问题,本文以历史地图《宁夏省境黄河沿岸沟渠水道地形图》为试验数据,提出一种智能化历史地图水系信息提取方法。首先,结合符号句法,运用聚类与数学形态学方法构建数据集;然后,改进通用大模型(SAM)结构并进行迁移学习优化权重;最后,借助改进SAM自动提取历史地图水系信息。将试验结果与其他模型作对比,显示本文方法提取结果边界清晰,轮廓完整,准确率、精度等指标均为最高。同时,将提取结果与该区域水系现状作对比,发现历史上的河流沟渠如今大多改道、偏移或消失,湖泊面积大大减小。本文方法基于SAM通用大模型进行改进,验证了大模型在地图领域的可用性,为地图信息提取提供了思路。 展开更多
关键词 历史地图 水系提取 模糊c均值聚类 数学形态学 SaM通用大模型
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Effectof Neutral Traps on Tunneling Current and SILC in Ultrathin Oxide Layer
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作者 张贺秋 毛凌锋 +1 位作者 许铭真 谭长华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第4期367-372,共6页
The effect of neutral trap on tunneling currentin ultrathin MOSFETs is investigated by num erical analy- sis.The barrier variation arisen by neutral trap in oxide layer is described as a rectangular potential well in... The effect of neutral trap on tunneling currentin ultrathin MOSFETs is investigated by num erical analy- sis.The barrier variation arisen by neutral trap in oxide layer is described as a rectangular potential well in the con- duction band of Si O2 .The different barrier variation of an ultrathin metal- oxide- sem iconductor(MOS) structure with oxide thickness of4nm is numerically calculated.It is shown that the effect of neutral trap on tunneling cur- rent can not be neglected.The tunneling current is increased when the neutral trap exists in the oxide layer.This simple m odel can be used to understand the occurring mechanism of stress induced leakage current. 展开更多
关键词 tunneling current high- field stress ULTRaTHIN SIL c
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模块化高压大容量DC/DC变换器综述 被引量:1
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作者 张书鑫 赵若凡 刘鸿鹏 《东北电力大学学报》 2024年第1期52-60,共9页
随着新能源发电占比增加和电网规模的不断扩大,直流输电系统的容量不断提升,含有不同电压等级的直流电网是未来发展的必然趋势。在此背景下,DC/DC变换器作为直流电网关键设备,在多电压等级互联场景中发挥着重要作用。文中首先对已有的... 随着新能源发电占比增加和电网规模的不断扩大,直流输电系统的容量不断提升,含有不同电压等级的直流电网是未来发展的必然趋势。在此背景下,DC/DC变换器作为直流电网关键设备,在多电压等级互联场景中发挥着重要作用。文中首先对已有的模块化高压大容量DC/DC变换器进行归纳、分类和比较,然后阐述了目前模块化高压大容量DC/DC变换器的拓扑结构、工作原理与特点,并针对其特点提出了不同变换器的适用场景,最后对未来的研究方向提出了建议。 展开更多
关键词 柔性直流输电 直流电网 模块化多电平换流器 模块化高压大容量Dc/Dc变换器
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基于剩余电流和不平衡电流突变向量比的TN-C-S系统漏电故障检测方法 被引量:1
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作者 翟国亮 梁栋 +3 位作者 王玮 徐丙垠 高海洋 尚同同 《中国电机工程学报》 EI CSCD 北大核心 2024年第5期1726-1736,I0005,共12页
TN-C-S系统在我国应用广泛,但由于固有剩余电流大,无法区分负荷投切和故障引起的剩余电流变化,漏电总保和中保无法投运,存在安全隐患。针对该问题,提出一种基于剩余电流和不平衡电流突变量之比的漏电故障保护方法。首先,分析剩余电流回... TN-C-S系统在我国应用广泛,但由于固有剩余电流大,无法区分负荷投切和故障引起的剩余电流变化,漏电总保和中保无法投运,存在安全隐患。针对该问题,提出一种基于剩余电流和不平衡电流突变量之比的漏电故障保护方法。首先,分析剩余电流回路,剩余电流和不平衡电流突变量之比在单相接地故障发生时刻突变,在负荷投切时不变。其次,基于中性线阻抗和接地阻抗不会发生突变的特征,计算故障电流突变量幅值,以故障电流突变量幅值越限作为故障判别依据,实现漏电故障检测。仿真及试验证明,所提方法可有效区分负荷投切和漏电故障,实现大幅值固有剩余电流下的漏电故障检测,在单支路和多支路系统中的检测灵敏度分别为70、150 mA,满足TN-C-S系统多级漏电保护的灵敏度要求。 展开更多
关键词 TN-c-S系统 漏电保护 剩余电流 不平衡电流 突变向量
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Diagnostic non-invasive model of large risky esophageal varices in cirrhotic hepatitis C virus patients 被引量:5
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作者 Hatem Elalfy Walid Elsherbiny +4 位作者 Ashraf Abdel Rahman Dina Elhammady Shaker Wagih Shaltout Ayman Z Elsamanoudy Bassem El Deek 《World Journal of Hepatology》 CAS 2016年第24期1028-1037,共10页
AIM To build a diagnostic non-invasive model for screening of large varices in cirrhotic hepatitis C virus(HCV) patients. METHODS This study was conducted on 124 post-HCV cirrhotic patients presenting to the clinics o... AIM To build a diagnostic non-invasive model for screening of large varices in cirrhotic hepatitis C virus(HCV) patients. METHODS This study was conducted on 124 post-HCV cirrhotic patients presenting to the clinics of the Endemic Medicine Department at Mansoura University Hospital for evaluation before HCV antiviral therapy: 78 were Child A and 46 were Child B(score ≤ 8). Inclusion criteria for patients enrolled in this study was presence of cirrhotic HCV(diagnosed by either biopsy or fulfillment of clinical basis). Exclusion criteria consisted of patients with other etiologies of liver cirrhosis, e.g., hepatitis B virus and patients with high MELD score on transplant list. All patients were subjected to full medical record, full basic investigations, endoscopy, and computed tomography(CT), and then divided into groups with no varices, small varices, or large risky varices. In addition, values of Fibrosis-4 score(FIB-4), aminotransferase-to-platelet ratio index(APRI), and platelet count/splenic diameter ratio(PC/SD) were also calculated.RESULTS Detection of large varies is a multi-factorial process, affected by many variables. Choosing binary logistic regression, dependent factors were either large or small varices while independent factors included CT variables such coronary vein diameter, portal vein(PV) diameter, lieno-renal shunt and other laboratory noninvasive variables namely FIB-4, APRI, and platelet count/splenic diameter. Receiver operating characteristic(ROC) curve was plotted to determine the accuracy of non-invasive parameters for predicting the presence of large esophageal varices and the area under the ROC curve for each one of these parameters was obtained. A model was established and the best model for prediction of large risky esophageal varices used both PC/SD and PV diameter(75% accuracy), while the logistic model equation was shown to be(PV diameter ×-0.256) plus(PC/SD ×-0.006) plus(8.155). Values nearing 2 or more denote large varices.CONCLUSION This model equation has 86.9% sensitivity and 57.1% specificity, and would be of clinical applicability with 75% accuracy. 展开更多
关键词 DIaGNOSTIc model large VaRIcES cirrhotic hepatitis c virus cOMPUTED tomography NONINVaSIVE variceal diagnosis
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Investigation of Ancient and Large Tree Resources in Green Spaces of Urban Parks: A Case Study of Yunqizhujing Park in Hangzhou, China 被引量:5
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作者 CHU Jiamiao LAI Shuifang +1 位作者 ZHONG Tailin LI Yuan 《Journal of Landscape Research》 2012年第10期51-54,共4页
Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environmen... Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environment and enriching urban humanistic and natural landscapes, and they were also important contents of urban garden works symbolizing urban parks. A case study was carried out Yunqizhujing Park to study conservation of ancient and large trees in park green spaces of Hangzhou City, solutions to current problems were proposed, and constructive suggestions were given for the conservation of ancient and large trees in urban park green spaces. 展开更多
关键词 PaRK green SPacES aNcIENT and large valuable TREE RESOURcES current situation Problems Solutions
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Hepatitis C virus and diffuse large B-cell lymphoma: Pathogenesis, behavior and treatment 被引量:6
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作者 Carlo Visco Silvia Finotto 《World Journal of Gastroenterology》 SCIE CAS 2014年第32期11054-11061,共8页
A significant association between hepatitis C virus (HCV) infection and B-cell lymphoma has been reported by epidemiological studies, most of them describing a strong relationship between indolent lymphomas and HCV. F... A significant association between hepatitis C virus (HCV) infection and B-cell lymphoma has been reported by epidemiological studies, most of them describing a strong relationship between indolent lymphomas and HCV. Furthermore, the curative potential of antiviral therapy on HCV related indolent lymphomas supports a specific role for the virus in lymphomagenesis. These observations are reinforced by numerous laboratory experiments that led to several hypothetical models of B-cell transformation by HCV. Diffuse large B-cell lymphoma (DLBCL), the most common lymphoma subtype in the western countries, has been associated to HCV infection despite its aggressive nature. This association seems particularly prominent in some geographical areas. Clinical presentation of HCV-associated DLBCL has consistently been reported to differ from the HCV-negative counterpart. Nevertheless, histopathology, tolerance to standard-of-care chemo-immunotherapy (R-CHOP or CHOP-like regimens) and final outcome of HCV-positive DLBCL patients is still matter of debate. Addition of rituximab has been described to enhance viral replication but the probability of severe hepatic complications remains low, with some exceptions (i.e., hepatitis B virus or immune immunodeficiency virus co-infected patients, presence of grade &#x0003e; 2 transaminases elevation, cirrhosis or hepatocarcinoma). HCV viral load in this setting is not necessarily directly associated with liver damage. Overall, treatment of HCV associated DLBCL should be performed in an interdisciplinary approach with hepatologists and hematologists with close monitoring of liver function. Available reports reveal that the final outcome of HCV-positive DLBCL that receive standard immunochemotherapy is not inferior to their HCV-negative counterpart. This review summarizes data on epidemiology, pathogenesis and therapeutic approach on HCV-associated DLBCL. Several issues that are matter of debate like clinical management of patients with transaminase elevation, criteria for discontinuing or starting immuno-chemotherapy, as well as the exact role of monoclonal antibodies will be analyzed. 展开更多
关键词 Hepatitis c virus Non-Hodgkin lymphoma Liver Toxicity Diffuse large B-cell lymphoma RITUXIMaB cYcLOPHOSPHaMIDE Hydroxydaunorubicin VINcRISTINE PREDNISOLONE Immuno-chemotherapy antiviral treatment
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Case report of acute-on-chronic liver failure secondary to diffuse large B-cell lymphoma 被引量:3
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作者 Yahuza Siba Kenechukwu Obiokoye +2 位作者 Richard Ferstenberg James Robilotti Joan Culpepper-Morgan 《World Journal of Gastroenterology》 SCIE CAS 2014年第44期16774-16778,共5页
Acute liver failure is a rare presentation of hematologic malignancy. Acute on chronic liver failure(ACLF) is a newly recognized clinical entity that describes acute hepatic decompensation in persons with preexisting ... Acute liver failure is a rare presentation of hematologic malignancy. Acute on chronic liver failure(ACLF) is a newly recognized clinical entity that describes acute hepatic decompensation in persons with preexisting liver disease. Diffuse large B-cell lymphoma(DLBCL) is an aggressive non-Hodgkin's lymphoma(NHL) with increasing incidence in older males, females and blacks. However, it has not yet been reported, to present with acute liver failure in patients with preexisting chronic liver disease due to human immunodeficiency virus(HIV)/hepatitis C virus(HCV) co-infection. We describe a case of ACLF as the presenting manifestation of DLBCL in an elderly black man with HIV/HCV coinfection and prior Hodgkin's disease in remission for three years. The rapidly fatal outcome of this disease is highlighted as is the distinction of ACLF from decompensated cirrhosis. Due to the increased prevalence of HIV/HCV co-infection in the African American 1945 to 1965 birth cohort and the fact that both are risk factors for chronic liver disease and NHL we postulate that the incidence of NHL presenting as ACLF may increase. 展开更多
关键词 Diffuse large B-cell lymphoma acute-on-chronic liver failure Human immunodeficiency virus Hepatitis c virus Hodgkin's disease Fatal outcome
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The Diagnostic and Prognostic Impact of Serum miRNA-21 in a Sample of Hepatitis C/None Hepatitis Diffuse Large B Cell Lymphoma Egyptian Patients 被引量:1
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作者 Nabil El-Halawani Aida Nazir +2 位作者 Nagwa Mashali Amani Sorour Mayada A. Moussa 《American Journal of Molecular Biology》 2017年第1期49-72,共24页
Background: Circulating microRNAs are potential biomarkers of diagnostic and prognostic impact in various inflammatory and malignant diseases. Aim: Linking inflammation with malignancy, we studied miRNA-21 in sera of ... Background: Circulating microRNAs are potential biomarkers of diagnostic and prognostic impact in various inflammatory and malignant diseases. Aim: Linking inflammation with malignancy, we studied miRNA-21 in sera of hepatitis-C-virus (HCV) and none hepatitis diffuse large B-cell lymphoma (DLBCL) patients, aiming to identify its differential expression and prognosis in DLBCL with its subtypes;germinal center B-cell (GCB) and activated B-cell-like (ABC) and to evaluate its relation with HCV. Subjects and Methods: MiRNA-21 expression was measured using TaqMan quantitative RT-PCR in sera of 30 newly diagnosed DLBCL patients (HCV positive (n = 10), HCV negative (n = 20)) and 20 controls (HCV positive (n = 10), HCV negative (n = 10)). Results: MiRNA-21 expression was significantly higher in DLBCL patients than in control (p = 0.00). Significant positive correlations between miRNA-21 and LDH, IPI and disease stage were detected (p Conclusion: Our study shows that miRNA-21 is over expressed in our patients with DLBCL, displaying higher levels in ABC than in GCB subtypes. MiRNA-21 is associated with poor response to treatment and survival in DLBCL. MiRNA-21 is a potential marker of necro-inflammation independent of its role in tumorogenesis, showing higher expression in HCV positive DLBCL patients compared to none hepatitis patients. 展开更多
关键词 Diffuse large B-cELL Lymphoma MIcRORNa-21 HEPaTITIS c Virus Germinal center-B activated B-cell-Like
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